When there is an improvement or increase in the value of currency of a particular then this will result in an appreciation of currency of that particular nation. This will affect the nominal exchange rate not the real exchange rate.
Nominal exchange rate refers to the rate at which currency of one nation is exchanged for another currency. Therefore, if there is any in the change in the value of a particular nation then this will affect the nominal exchange rate.
1- Great Depression- wheat or rice 2- Colonial period- indigo 3- Reconstruction Era- Tobacco 4- Silk- <span>Post-World War II </span> Take these answers with a grain of salt. I am doing my best. But it has been a little while since I took that class.